It is a known technology that a fuel consumption of an internal combustion engine (engine) is improved by supplying an evaporation fuel (equivalent to evaporation gas) that is not combusted to an intake pipe of the engine. For example, Patent Literature 1 discloses a device which temporarily collects the evaporation fuel that is generated by an evaporation of a fuel in a fuel tank at a canister and supplies the evaporation fuel to the intake pipe. The evaporation fuel is supplied from the canister to the intake pipe through a purge pipe connected with the canister and the intake pipe. A purge of the evaporation fuel from the canister is executed by using a negative pressure generated by an air that is used in a combustion and flows through the intake pipe. The device according to Patent Literature 1 executes a diagnosis of a supply system of the evaporation fuel including the canister. Specifically, the device senses a pressure in the fuel tank and diagnoses whether an abnormality of the supply system exists based on the pressure.